The present invention relates to laminate sheet materials. The laminate sheet materials are useful, for example, for fire barrier applications on vehicles such as aircraft.
There are a variety of situations where it is necessary or desirable to utilize a barrier to prevent or reduce the transfer of heat and/or flame. For example, the fuselage of an aircraft generally includes a metal outer skin supported around a metal frame comprising a stringer and circumferential members. Since temperatures within the fuselage must usually be controlled in order to insure the proper environment for occupants and cargo, most fuselage shells also include some form of thermal insulation. Insulation is generally included for acoustical reasons as well. In many aircraft this insulation takes the form of fiberglass batts supported by the stringer and circumferential members.
The fiberglass is generally encased in a film bagging material to protect the fiberglass from condensate and other fluids the insulation might come into contact with. Bagging materials that have been used for such a purpose include metallized polyester, plain polyester, metallized polyvinyl fluoride, and polyimide.
In 2000, the FAA (i.e., the United States Federal Aviation Administration) issued notice of proposed rule making detailing new test methods for thermal/acoustic insulation intended to increase in-flight fire safety and post-crash burn-through resistance of insulation materials on aircraft. The FAA published an Airworthiness Directive requiring operators of hundreds of aircraft to replace insulation blankets covered with metallized polyester within the next four years. Replacement materials are to meet the FAA""s new in-flight fire protection test, which is based on the American Society for Testing, and Materials test designated as ASTM E 648-97, Mar. 10, 1999. The disclosure of which is incorporated herein by reference. The FAA has drafted a proposed requirement that would mandate both enhanced in-flight fire resistance and post-crash burn through protection (see, e.g., Department of Transportation, Federal Aviatioin Administration, Improved Flammability Standards for Thermal/Acoustic Insulation Materials Used in Transport Category Airplanes; Proposed Rule, 14 CFM Part 25, et al., Federal Register, Vol. 65, No. 183, Wednesday, Sep. 20, 2000, pp. 56992-57022, the disclosure of which is incorporated herein by reference).
There exists a need for additional insulation materials and associated flame and/or fire protection materials. Preferably, these materials meet one or more of the applicable industry and/or government standards for a particular use.
The present invention provides a laminate sheet material comprising a first layer comprised of polymeric material and a second layer comprised of non-metallic fibers. The first and second layers at least collectively contribute to the laminate sheet material having at least one of a passing Flammability Value I, (i.e., if the laminate sheet material is subjected to the Flammability Test I defined herein, it will have a passing Flammability Value I), a passing Flammability Value II, (i.e., if the laminate sheet material is subjected to the Flammability Test II defined herein, it will have a passing Flammability Value), a passing Flame Propagation Value I (i.e., if the laminate sheet material is subjected to the Flame Propagation Test I defined herein, it will have a passing Flame Propagation Value I), a passing Flame Propagation Value II, (i.e., if the laminate sheet material is subjected to the Flame Propagation Test II defined herein, it will have a passing Flame Propagation Value II), or a passing Burnthrough Value (i.e., if the laminate sheet material is subjected to the Burnthrough Test as defined herein, it will have a passing Burnthrough Value). For some preferred embodiments of laminate sheet material according to the present invention, the first and second layers are sufficient to collectively provide the laminate sheet material having at least one of a passing Flammability Value I, a passing Flammability Value II, a passing Flame Propagation Value I, a passing Flame Propagation Value I, or a passing Burnthrough Value. The tests determining a passing Flammability Value I, a passing Flammability Value II, a passing Flame Propagation Value I, a passing Flame Propagation Value II, and a passing Burnthrough Value are described below under the heading xe2x80x9cTEST PROCEDURESxe2x80x9d.
In another aspect, the present invention also provides a system for limiting exposure of flammable insulation material to an ignition source comprising:
laminate sheet material comprising:
a first layer comprised of polymeric material; and
a second layer comprised of non-metallic fibers,
wherein the laminate sheet material is positioned between the flammable insulation material and the ignition source such that the first layer of the laminate sheet material is adjacent to the flammable insulation material. The first and second layers at least collectively contribute to the laminate sheet material having at least one of a passing Flammability Value I, a passing Flammability Value II, a passing Flame Propagation Value I, a passing Flame Propagation Value II, or a passing Burnthrough Value. For some preferred embodiments of laminate sheet material according to the present invention, the first and second layers are sufficient to collectively provide the laminate sheet material having at least one of a passing Flammability Value I, a passing Flammability Value II, a passing Flame Propagation Value I, a passing Flame Propagation Value II, or a passing Burnthrough Value. The tests determining a passing Flammability Value I, a passing Flammability Value II, a passing Flame Propagation Value I, a passing Flame Propagation Value II, and a passing Burnthrough Value are described below under the heading xe2x80x9cTEST PROCEDURESxe2x80x9d.
Flammable insulation material refers to insulation material that is inherently flammable; insulation material that has been rendered flammable at least in part due to contamination with a material that renders it flammable (e.g., fuel, hydraulic fluids, and corrosion inhibitors), as well as insulation material that may or may not be inherently flammable but that has a flammable cover or layer thereon (e.g., a metallized polyester cover).
In another aspect, the present invention also provides an insulation system comprising:
laminate sheet material comprising:
a first layer comprised of polymeric material; and
a second layer comprised of non-metallic fibers; and
insulation material;
wherein the laminate sheet material and the insulation material are positioned such that the first layer of the laminate sheet material is adjacent to the insulation material. The first and second layers at least collectively contribute to the laminate sheet material having at least one of a passing Flammability Value I, a passing Flammability Value H, a passing Flame Propagation Value I, a passing Flame Propagation Value II, or a passing Burnthrough Value. For some preferred embodiments of laminate sheet material according to the present invention, the first and second layers are sufficient to collectively provide the laminate sheet material having at least one of a passing Flammability Value I, a passing Flammability Value II, a passing Flame Propagation Value I, a passing Flame Propagation Value II, or a passing Burnthrough Value. The tests determining a passing a passing Flammability Value I, a passing Flammability Value II, a passing Flame Propagation Value I, a passing Flame Propagation Value II, and a passing Burnthrough Value are described below under the heading xe2x80x9cTEST PROCEDURESxe2x80x9d. The insulation material may be flammable or nonflammable.
In another aspect, the present invention also provides an insulation blanket comprised of:
laminate sheet material comprising:
a first layer comprised of polymeric material; and
a second layer comprised of non-metallic fibers; and
insulation material;
wherein the laminate sheet material and insulation material are positioned such that the first layer of the laminate sheet material is positioned adjacent to the insulation material. The first and second layers at least collectively contribute to the laminate sheet material having at least one of a passing Flammability Value I, a passing Flammability Value II, a passing Flame Propagation Value I, a passing Flame Propagation Value II, or a passing Burnthrough Value. For some preferred embodiments of laminate sheet material according to the present invention, the first and second layers are sufficient to collectively provide the laminate sheet material having at least one of a passing Flammability Value I, a passing Flammability Value II, a passing Flame Propagation Value I, a passing Flame Propagation Value II, or a passing Burnthrough Value. The tests determining a passing Flammability Value I, a passing Flammability Value II, a passing Flame Propagation Value I, a passing Flame Propagation Value II, and a passing Burnthrough Value are described below under the heading entitled xe2x80x9cTEST PROCEDURESxe2x80x9d. The insulation material may be flammable or nonflammable.
The present invention is useful, for example, in a variety of situations where it is necessary or desirable to utilize a material or system to prevent or reduce the transfer of heat and/or flame. For example, embodiments according to the present invention can be utilized in the production of new aircraft and/or retrofitting existing aircraft to protect flammable material from potential ignition sources (e.g., short circuits from electrical wiring). For existing aircraft, laminate sheet material according to the present invention may be placed, for example, over the existing aircraft insulation material (typically a flammable insulation material) such that it is between the insulation material and a potential ignition source to reduce exposure of the insulation material from the ignition source.
The present invention also provides a vehicle comprising insulation material and a laminate sheet material according to the present invention, wherein the laminate sheet material and the insulation material are positioned such that the first layer of the laminate sheet material is positioned adjacent to the insulation material. The insulation material may be flammable or nonflammable.
The present invention also provides an aircraft comprising insulation material, electrical wiring, and laminate sheet material according to the present invention, wherein the laminate sheet material is positioned between the insulation material and electrical wiring, and wherein the first layer of the laminate sheet material is adjacent to the insulation material. The insulation material may be flammable or nonflammable.
The present invention also provides an aircraft comprising insulation material, a fuselage exterior skin, and laminate sheet material according to the present invention, wherein the laminate sheet material is positioned between the insulation material and the fuselage exterior skin, and wherein the first layer of the laminate sheet material is adjacent to the flammable insulation material. The insulation material may be flammable or nonflammable.